Authentic flavors and ridiculous prices are a potent combination, and nobody packs that one-two punch like Ricos Tacos Lupe, a tiny fluorescent-orange storefront on Southwest Boulevard. Street tacos -- soft, warm corn tortilla rounds with a choice of traditional fillings -- cost $1 on Tuesdays, $1.50 other days. They are smaller in size than typical Tex-Mex versions, and three will fill you up.